The flow system is driven by seven stainless steel syringes (Harvard Apparatus) each connected to a computer-controlled syringe pump (Harvard Apparatus, PhD Ultra and Chemyx, Fusion 4000 Syringe Pump). The channels connecting the syringe to the flow junctions are 50 cm each of 0.01 in ID fluorinated ethylene propylene (FEP) tubing, and the PFO and SQD delivery channels are both intersected by a selector valve (VICI, C25-3180EUHB), which provides the option to redirect flow to the respective refill vessel.
The zinc halide and ligand mixtures are combined within two PEEK cross-junctions (IDEX-H&S, P-722) connected in series followed by a 10 cm, 0.01 in ID, FEP passive micromixer. This mixture is directed into a tee-junction (IDEX-H&S, P-715) to combine with the SQD channel which is followed by a second micrometer. The homogenous reactive solution is finally combined in a second tee-junction with PFO for isolated droplet formation. The reactor section is comprised of 150 cm of 0.03 in ID FEP followed by the reduced path length flow cell. Optical sampling is conducted using a miniaturized fiber-coupled spectrometer (Ocean Optics, HDX UV-Vis), 5 deuterium halogen lamp (Ocean Optics, DH-2000-BAL), and 365 nm high power light-emitting diode (Thorlabs, M365LP1) all connected to the flow cell through fiber optic patch
cords (Ocean Optics, QP600-1-SR).